I'm a PHP Newbie: I want to check if the referer is from a certain domain

What I want to do: When a user views the page, I want to check whether they're coming from another page on my site or whether this is the first page that they're viewing. If it's the first page, then I want to echo some code to the browser (it will read the cookie file for my site) This is the code that I tried to use: [code] global $HTTP_REFERER; $refp = parse_url($HTTP_REFERER); $refr = $refp[host]; if ($refr != "rideau.prowsej.com") { echo "insert javascript here that the browser will execute"; } [/code] - My domain is rideau.prowsej.com - The above code didn't seem to work. It seemed that a lot of the time, the referer was null. Under what conditions would the referer be null (where could I read about the $HTTP_REFERER variable?) Any help is much appreciated. Thanks. - Joshua Prowse Rideau High School Student